The present invention relates to apparatus and method for heating floor tiles for removal from subflooring, and more particularly to such apparatus and method which is adapted to heat, lift and store asbestos floor tile without discharging asbestos particles into the air.
The heating of floor tiles to facilitate their removal from an underfloor or subfloor is well known. However, such heating has not been accompanied by the appropriate safeguards and techniques which would make the same useful in the removal of asbestos floor tile as well as more efficient in the removal of floor tile of other materials. First, all portions of the entire upper surface of the floor tile could not be heated simultaneously to bring the entire floor tile and the thermoplastic adhesive or mastic thereunder to a generally uniform temperature across its width and length. Such a thorough horizontal heating is necessary to enable removal of the tile as an unbroken intact unit from the underfloor which is particularly important when removing asbestos tiles. Second, the temperature of the heating means could not be varied to provide appropriate heating for a particular tile and mastic. Such a variable temperature heat control is desirable because particular tiles and mastics may differ in composition, thickness, and the like from one floor to another. Third, the temperature of the upper surface of the tile was not monitored continuously to insure that it did not exceed a predetermined level. Depending upon the composition of the particular floor tile and such other factors as the materials with which it has been waxed or otherwise treated, the tiles must be maintained below a particular temperature at which poisonous or otherwise hazardous or deleterious fumes (such as hydrogen chloride, vinyl chloride or the like) are produced. Additionally, where it is desired that the upper surface of the tile be maintained in a relatively smooth and unblistered state to facilitate its subsequent removal, as described hereinbelow, the temperature must be maintained below that which would produce blistering or bubbling of the upper tile surface. Fourth, a dwell period was not provided after heating of the tile was terminated but before an attempt was made to remove the tile from the underflooring. Such a dwell period is necessary in certain instances in order to achieve thorough vertical heating, i.e., to allow the heat to pass from the upper surface of the tile vertically through the thickness of the tile and into the mastic therebelow to ensure the desired thorough softening of the mastic, as well as thorough softening of the tile itself, so that the tile may be removed easily and handled intact during the removal process without breakage thereof.
The Asbestos Hazard Emergency Response Act of 1986 mandates the removal of asbestos-containing materials from schools, and there is pending legislation to expand the requirements to various commercial and public buildings. Once regarded highly for its fireproofing and insulating properties, asbestos is now in disfavor because high doses of asbestos particles (e.g., fibers or powders) have been found to scar the lungs, causing cancer and other diseases. Much of the asbestos material is used in a friable state in which the material can turn to particles under simple hand pressure, crumbling into microscopic fibers or powder that can float through the air.
Asbestos tile flooring, containing up to 20% by weight of asbestos, is typically placed on top of subflooring or underflooring, which may consist of concrete or wood, using a thermoplastic adhesive, called a mastic, to secure the tile in place on top of the subflooring. Conventional attempts to remove such tiles frequently result in the tile being broken into pieces so that asbestos particles are released into the air and contaminate the entire area. More particularly, the conventional method of removing asbestos tiles from the subflooring, so as to enable placement of new floor covering, consists of chipping the asbestos tile off the subflooring. Statutes, agency regulations, and simply a concern for the potential legal liability dictate that the work area be shielded with containment apparatus, that personnel dress in protective gear and wear masks, and the like, all of which increase the number of personnel and the time required per job site, and thereby the overall cost of the removal operation. Accordingly, there is a need for apparatus and methods for the removal of the asbestos floor tile in a manner which leaves the asbestos tile intact so that release of asbestos particles therefrom to the air is minimized. Additionally, the apparatus should further remove the tiles from the floor and stack them in disposable containers so as to minimize contact of the apparatus operator with the tiles.
It is a primary object of the present invention to provide apparatus for the heating of floor tile to facilitate its removal from underflooring with appropriate safeguards and techniques to provide a uniform, safe and thorough heating of the floor tile and the mastic securing it to the underflooring.
It is a particular object of the invention to provide a heater which insures uniform heating of the tiles over its entire surface area.
It is also an object of the present invention to provide apparatus for the heating, lifting and storage of floor tile from underflooring without breakage of the tile.
A further object of the invention is to provide such apparatus which not only removes the floor tile from the underflooring, but automatically relocates it into a disposable storage container.
Yet another object of this invention is to provide such apparatus which is especially suited for the removal of asbestos floor tile because it minimizes the discharge of asbestos particles into the air.
It is a further object of the present invention to provide such apparatus which is relatively simple and economical to manufacture, to maintain, and to operate.